MCP server: find the right paid x402 API for a task, plus pay-per-call fact checks for AI agents (IBAN, EU VAT, OFAC sanctions, LEI, phone, email, FX, WHOIS) via x402 USDC on Base. Also the shared core of base-memecoin-guard-mcp.
Wellknown found it in public sources; nobody has proven control of it yet. Claiming takes one click if the repository is under your GitHub account, or a small file on your domain otherwise. Verified owners get the badge, 15-minute checks, status alerts, edits that outrank crawled data, and a ranking boost.
Agents can do it too: POST https://wellknown.network/api/v1/claims with {"agent":"facts402-mcp","method":"well_known_file"} — machine-readable steps at claim.json, guide at /docs/claim.
Everything here was measured by our prober or read from a registry. Nothing is self-reported.
Attributed to the source that supplied each field. Treated as claims, not facts.
# facts402-mcp <!-- mcp-name: com.facts402/facts402-mcp --> **Find the right paid API for a task, and verified fact checks for AI agents.** Before an agent pays an unknown API, `x402_recommend` ranks the x402 endpoints that fit the task by relevance, real on-chain buyers and liveness, for $0.005 (the preview is free). And at $0.01 per call: validate an IBAN before a payout. Check an EU VAT number in VIES before invoicing. Screen a name against OFAC sanctions. Look up a company's LEI. Validate a phone number or email before outreach. Convert currency at official ECB rates. Check how old a domain is. These are small, exact answers an agent can rely on, with no API keys or sign-up. Pay per call with [x402](https://x402.org): USDC on Base, from **your own wallet**, within a per-call cap and a session budget you set. ## Tools | Tool | Price (USDC) | Use it to | |---|---|---| | `x402_recommend` | $0.005 | Find the best paid x402 endpoints for a task: url, price, network, 30-day buyers, liveness, risk flags, score | | `x402_recommend_preview` | free | See the single top pick (host, price, buyers) for a task | | `iban_check` | $0.01 | Validate an IBAN and get bank name, BIC and SEPA membership | | `eu_vat_check` | $0.01 | Check an EU VAT number in VIES: status, company name and address | | `sanctions_screen` | $0.01 | Fuzzy-screen a person, company, vessel or aircraft against the OFAC SDN list | | `lei_lookup` | $0.01 | Look up a company in the GLEIF LEI index, by LEI or by name | | `phone_check` | $0.01 | Validate and normalise a phone number: E.164, line type, carrier, time zone | | `email_check` | $0.01 | Check email syntax, MX, disposable and role-account flags | | `fx_convert` | $0.01 | Convert currency at ECB reference rates, for the latest day or any of the last 90 | | `domain_check` | $0.01 | Get a domain's age, registrar, status and DNSSEC via RDAP (WHOIS) | | `business_days` | $0.01 | Count business days and list public holidays between two dates | | `weathe…
Mapped onto the structured taxonomy from declared text and observed tool names. Confidence shown for derived entries.
Every source is kept verbatim. Field changes are logged as events.